Dietary calcium and blood pressure in a Native American population.
OBJECTIVE
To assess the relationship between dietary calcium and blood pressure.


METHODS
Cross-sectional study of 404 adult Pima Indians of Arizona. Dietary variables were assessed by the 24-hour recall. Hypertension (HTN) was defined as systolic blood pressure (SBP) > or = mmHg or diastolic blood pressure (DBP) > or = 90 mmHg or drug treatment.


RESULTS
Controlled for age and sex, dietary calcium intake was higher in subjects with HTN than in those without (p < 0.01), and higher dietary calcium was associated with a higher prevalence of HTN (odds ratio comparing highest with lowest tertile group of calcium = 2.6, 95% CI 1.4-4.8). Age-sex-adjusted men DBP in low, middle and high tertiles of calcium was 74, 76, and 79 mmHg, respectively (p < 0.001). SBP was not significantly different in the three tertiles (p = 0.07). Multiple regression analyses that controlled for age, sex, body mass index, sodium, potassium and alcohol also suggested a positive association between DBP and dietary calcium (p < 0.01), an association which was stronger at higher glucose concentrations (p < 0.01 for the calcium-glucose interaction).


CONCLUSIONS
In Pima Indians, a population with a high incidence of diabetes, the inverse association between dietary calcium and blood pressure reported in other populations was not found.
Narayan
K M
KM
Diabetes and Arthritis Epidemiology Section, Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, Arizona, USA.
Hanson
R L
RL
Smith
C J
CJ
Nelson
R G
RG
Gyenizse
S B
SB
Pettitt
D J
DJ
Knowler
W C
WC
D000293:Adolescent; D000328:Adult; D000368:Aged; D000428:Alcohol Drinking; D001130:Arizona; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D015992:Body Mass Index; D002136:Calcium, Dietary / Q000008:administration & dosage*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology; D003971:Diastole; D004041:Dietary Fats / Q000008:administration & dosage; D004043:Dietary Fiber / Q000008:administration & dosage; D002149:Energy Intake; D005260:Female; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D007198:Indians, North American; D008297:Male; D008875:Middle Aged; D008903:Minerals / Q000008:administration & dosage; D011446:Prospective Studies
D001786:Blood Glucose; D002136:Calcium, Dietary; D004041:Dietary Fats; D004043:Dietary Fiber; D008903:Minerals